| 摘要 |
The invention discloses a drafting ruler that includes a straight ruler, a parallel ruler and a protractor, and the straight ruler includes a groove with a scale at the middle and an arc fixing groove using an end of the groove as the center. The protractor includes a semicircular protrusion corresponding to the fixing groove at the center of said straight ruler for movably connecting the straight ruler, such that the protractor can work with the groove of the straight ruler to draw an oblique line with an inclined angle, and can quickly draw several parallel lines or perpendicular lines starting from the mid-point to the length of the line by using the movably and perpendicularly connected straight ruler and parallel ruler, so that users can draw different figures or tables quickly and conveniently.
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